Alkylation Technology

STRATCO® Alkylation Technology


The STRATCO® Alkylation Technology is a sulfuric acid catalyzed process that converts low-value, straight-chain olefins into high-value, branched components called alkylate. Alkylate, with its superior blending properties, is a key component for clean gasoline. 

With over 100 licensed units worldwide, the STRATCO® Alkylation Technology helps refiners safely produce cleaner-burning gasoline with high octane, low RVP, low sulfur, zero aromatics and zero olefins. 

Process Technologies
Process Technologies
World-leading STRATCO® sulfuric acid alkylation solutions yield cleaner-burning gasoline with high octane, low RVP, low sulfur and zero olefins.
Comprehensive services from Elessent experts for existing sulfuric acid alkylation units in refineries
Engineered equipment for best-in-class performance and reliability

STRATCO® Alkylation Technology
Process Description


The STRATCO® Alkylation Technology combines propylene, butylenes and/or amylenes, either individually or as a mixture, with isobutane in the presence of a strong sulfuric acid catalyst to produce high-octane, branched chained hydrocarbons for use in motor fuel and aviation gasoline. Olefins and isobutane-rich streams along with a catalyst stream of sulfuric acid are charged to the STRATCO® Contactor™ reactor.

The liquid contents of the Contactor™ reactor are circulated to create an optimized amount of interfacial area between the reacting hydrocarbons and the acid catalyst from the acid settler. This circulation ensures the entire volume of liquid in the Contactor™ reactor is maintained at a uniform temperature. The STRATCO® Alkylation Technologyis effluent refrigerated to remove the heat of reaction using a refrigeration section consisting of a compressor and depropanizer to remove excess propane.

The Contactor™ reactor products pass through a flash drum, are treated for removal of possible entrained sulfur species, and are fractionated in a deisobutanizer. The overhead from the deisobutanizer combines with the effluent refrigerant recycle to provide isobutane to the reaction zone and to promote the alkylation reaction. The deisobutanizer bottoms are further fractionated into normal butane (if applicable) and whole alkylate products. Technology to provide onsite sulfuric acid regeneration (SAR) for the STRATCO® Alkylation Technology is also available by license from Elessent.

The Benefits of
STRATCO® Alkylation Technology


The STRATCO® Alkylation Technology produces the highest-quality alkylate in a flexible and highly reliable process with proven best-in-class operations based on decades of supporting data. 

Feed Flexibility

Optimized Reaction Zone

  • Proven best-in-class product quality
  • Lowest CAPEX and OPEX sulfuric acid Alkylation Technology

Proven Record of Reliability

  • Units built in 1940s are still in operation
  • Commercial alkylation units consistently make a 4‐ to 5-year turnaround plan cycle
  • Unit successfully restarted after being shut down for 20 years

Find out more about STRATCO® Alkylation Technology innovations by clicking the button below. 

STRATCO® Alkylation Technology Overview Video

Find out how we can help you

Share this page